Present Perfect Tense (現在完成式)

主詞為I, you, we, they時，助動詞為 have

主詞為he, she, it時，助動詞為 has (第三人稱單數)

I have = I've

you have = you've

we have = we've

they have = they've

have not= haven't

has not= hasn't

Has he finished his homework?

Has Sandy watched/ seen the movie?

肯定句可加入already (句中或句尾) 或 just (句中)

 She has already arrived. or  She has arrived already.

We have just eaten the soup.

I haven’t said no yet.

Have you talked to him yet ?

過去式：I saw the movie the other day. --> 強調過去某時間看過

現在完成式：I have seen the movie twice. --> 強調已經看過 (經驗)

They have lived in Taiwan for twenty years.

The students have learned English since 2009.

I have known Linda since I was six years old.

The teacher has been in the classroom since ten minutes ago.

How long have you taught them?

It has been hot recently. 

Have I told you lately that I love you?

be動詞表示存在狀態，與地點合用，表示曾經處於某地

My sister has been to Paris. 去過日本，表示經驗，現在人已經回來了

go是動作，從一點移置另一點，並且是遠離說話者，所以完成式代表已經離開原地到另一地

My sister has gone to London. 已經前往倫敦，可能在飛機上或以到達倫敦，不在說話者所處的地方

Alien died in 2020. --> 強調過去時間點過世

The man has just died. --> 動作完成，表示剛死

Kobe has been dead for two years. --> 強調死去的狀態，從過去時間延伸到現在